The present invention relates to a pneumatic nail gun, and particularly to a pneumatic nail gun having an upper slidable sleeve valve and a lower slidable sleeve valve.
The pneumatic nail gun generally utilizes a compressed high pressure air to drive nails to punch, which is a gun-shaped pneumatic tool. The general structure and function of a nail gun is briefly introduced as follows. A nail gun has a gun body, the gun body having a gun handle and a gun head; a fastening cylinder disposed in the gun head; a high-pressure gas pipe coupled to one end of the gun handle, and a high-pressure gas being input and introduced into the cylinder; a piston disposed in the cylinder, the piston connected to a nail shooting mechanism at the external end of the gun head, and the nail shooting mechanism coupled to a nail magazine. When the gun body is triggered, and the piston is pushed downward by the compressed high pressure air such that the nail shooting mechanism can shoot out the nail at the nailing position. In addition, an air chamber is provided at an outer peripheral surface of the cylinder, which receives high pressure air from the cylinder to drive the piston to its original position when the piston moves its lower dead center.
However, the air chamber just can receive the high pressure air when the piston moves downward and can not receive high pressure air during the piston moves upward. Thus, the collection of the high pressure air in the air chamber for upward movement of the piston is limited, and the stability of the upward movement of the piston is lower. Especially, in the process of continuous nail punching, the instability upward movement of the piston lowers the speed and efficiency of nail punching.
For resolving the question, one method of adding the cubage of the air chamber is provided in recently technology. However, the method still is not an ideal resolution.
Accordingly, what is needed is a pneumatic nail gun that can overcome the above-described deficiencies.